US4564790A - Flat electron beam tube having a gas discharge as electron source - Google Patents

Flat electron beam tube having a gas discharge as electron source Download PDF

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Publication number
US4564790A
US4564790A US06/505,308 US50530883A US4564790A US 4564790 A US4564790 A US 4564790A US 50530883 A US50530883 A US 50530883A US 4564790 A US4564790 A US 4564790A
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electron
gas discharge
conductors
post
row
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US06/505,308
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Werner Veith
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Siemens AG
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Siemens AG
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Assigned to SIEMENS AKTIENGESELLSCHAFT, BERLIN AND MUNCHEN, GERMANY, A CORP OF reassignment SIEMENS AKTIENGESELLSCHAFT, BERLIN AND MUNCHEN, GERMANY, A CORP OF ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: VEITH, WERNER
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J17/00—Gas-filled discharge tubes with solid cathode
    • H01J17/38—Cold-cathode tubes
    • H01J17/48—Cold-cathode tubes with more than one cathode or anode, e.g. sequence-discharge tube, counting tube, dekatron
    • H01J17/49—Display panels, e.g. with crossed electrodes, e.g. making use of direct current
    • H01J17/498—Display panels, e.g. with crossed electrodes, e.g. making use of direct current with a gas discharge space and a post acceleration space for electrons

Definitions

  • the invention relates to a flat electron beam tube having a gas discharge as electron source and more particularly to such a beam tube which includes a gas-filled enclosure containing two mutually parallel plates, namely a front plate and a rear plate disposed one behind the other in viewing direction; the enclosure having an interior space subdivided by a control plate extending parallel to the planes of the front and the rear plates, into a front chamber; post-acceleration space, and a rear chamber defining a gas discharge space; the rear plate carrying at least one cathode on an inner side thereof, the cathode being a gas discharge cathode; the front plate carrying, on an inner side thereof, a luminescent layer excitable by electrons and a post-acceleration anode; the control plate carrying, on a side thereof facing towards the gas discharge space, a family of mutually parallel strip-shaped row conductors, and being formed with a number of regularly arranged electron inlet openings and, on the side thereof facing towards the post-acceleration space, a
  • ions are produced in the post-acceleration space.
  • These charge carriers when striking parts of the vessel, such as the sensitive electrode matrix, for example, sputter away material which may be deposited, in turn, on insulating paths or on the fluorescent screen and may then impair the dielectric strength thereof against high voltage and the light yield thereof, respectively.
  • the ions will pass into the gas discharge space and there increase the plasma current to such an extent that the tube will break down in this region.
  • a further source of trouble are fast electrons from the gas discharge space which pass through the electrode matrix outside the row or line then being controlled and thereby brighten the picture background.
  • a second line grid which, if addressed correctly, keeps the fast electrons from the post-acceleration space and thus reduces, particularly, the cross-talk effect in the columns and, in front thereof, an electrode at a fixed potential which divides the potential in the post-acceleration space in a non-linear manner and reduces the danger of a breakdown note in this connection
  • U.S. Pat. No. 4,322,657 which issued Mar. 30, 1982 and co-pending Application Ser. No. 470,702, filed Feb. 28, 1983, and assigned to the same assignee as that of the instant application.
  • Such a pentode requires a specific expense for manufacturing and adjustment, which becomes ever more critical with decreasing picture element spacing and, in addition, does not yet afford optimum contrast because plasma radiation can reach the display surface, as before.
  • a flat electron beam tube comprising: a gas-filled enclosure containing two mutually parallel plates, namely a front plate and a rear plate disposed one behind the other in viewing direction; the enclosure having an interior space subdivided by a control plate extending parallel to the planes of the front and the rear plates, into a front chamber, a post-acceleration space, and a rear chamber defining a gas discharge space; the rear plate carrying at least one cathode on an inner side thereof, the cathode being a gas discharge cathode; the front plate carrying, on an inner side thereof, a luminescent layer excitable by electrons and a post-acceleration anode; the control plate carrying, on a side thereof towards the gas discharge space, a family of mutually parallel strip-shaped row conductors, and being formed with a number of regularly arranged electron inlet openings and, on the side thereof facing towards the post-acceleration space,
  • a control plate constructed in accordance with the invention acts and appears opaque in a plan view because the openings on the one side of the plate are covered up by strips or slats on the other side of the plate; it is therefore clear that this plate does not at any point permit passage of ultraviolet or visible radiation from the plasma. Less obvious is the fact, initially, that the control plate with its curved passage channels also intercepts interfering charge carriers, but is permeable to useful electrons. This discriminator effect which has already been fully confirmed by experiment, can be explained as follows: the useful electrons i.e. the plasma electrons focused to the row just being addressed, are relatively slow.
  • the deflection fields prevailing ther towards the side (the opposite strip or slat being at sufficiently negative potential), and indeed, for the most part, so far that they come under the influence of the suction effect of the acceleration field extending through the gap openings and are therefore drawn altogether in a curved trajectory into the post-acceleration space.
  • the potential conditions or characteristics may be selected so that only relatively few useful electrodes, which fly through the center of the inlet opening, are intercepted by the strip or slat. This fate, on the other hand, is experienced by the greater part of the fast electrons, the trajectories of which are naturally "stiff" and can be curved rather nonappreciably by the deflection fields.
  • the ions which penetrate into the control space bounce, if they have absorbed relatively much energy, onto the strips or slats on the row side and are otherwise directed, to a greatly predominating extent, onto the strips or slots in the column plane. Only a few of the ions are capable of passing into the gas discharge space; breakdowns therefore do not occur.
  • the decoupling obtained with the covered control plate is so good that considerable latitude has been regained in the choice of the gas mixture and the gas pressure, as well as in the design of the cathode.
  • a circumstance which is also favorable is that the electron beams entering the post-acceleration space are already focused rather well so that, at most, only simple post-focusing may be required to recombine corresponding partial beams into a single beam having a small cross section. Added to this is that the row openings can be enlarged and the electron yield increased thereby without having to tolerate dangerous voltage penetration.
  • the display construction proposed herein has a control characteristic which considerably facilitates the maintenance of an overall uniform picture brightness, especially if the gray steps are to be generated by pulse-length modulation: with increasing control voltage, the screen current approaches a plateau which is virtually constant over wide voltage ranges.
  • the electron inlet and electron outlet are holes formed in the rows and columns, respectively.
  • a control structure in which hole-free line conductors (ribbons, wires) alternate with electron inlet gaps of approximately the same width has an additional advantage: the electrons which are drawn from the plasma and fly past the keyed-on row to the left and right are combined (by transverse fields in the inlet gaps) while yet in the control space to form a beam parallel to the rows.
  • an electron-optical cylinder lens should be provided in association with each column conductor.
  • Such a lens which, for one, cares for the post-focusing and, for another, shields the individual column conductors from one another, can be realized in an individual case by one or two conductor runs per column conductor parallel to the columns.
  • the electron inlet openings are formed by holes in the row conductors, and the electron outlet openings by holes in the column conductors, the electron outlet openings being disposed in offset relationship to the electron inlet openings with which they are associated in direction of extension of the row conductors.
  • the electron outlet openings are formed as slits extending perpendicularly to the direction of the offset.
  • the electron inlet openings are formed as longitudinal slits between adjacent row conductors, and the electron outlet openings are disposed in offset relationship, in direction of the extension of the column conductors to the electron inlet openings with which they are associated.
  • the electron outlet openings are formed as longitudinal slits located between adjacent column conductors, and the electron outlet openings are disposed offset in direction of the extension of the new conductors relative to the electron outlet openings with which they are associated.
  • a system of focusing electrodes having a potential negative with respect to the potential of the respective associated column conductor is arranged for focusing the electrons entering the post-acceleration space in a manner like that of an elecrtron-optical cylinder lens.
  • At least one strip-shaped focusing electrode associated with each column conductor and extending parallel thereto.
  • FIG. 1 is a perspective view partly broken-away and partly in section of an embodiment of the flat electron beam tube having a gas discharge as electron source according to the invention.
  • FIG. 2 is a cross-sectional view of the control plate of FIG. 1 taken along the line II--II, the support structure for the electrode matrix being merely indicated schematically.
  • FIG. 1 there is shown a flat picture screen containing a gas-filled jacket or shell 1 with a back plate 2 and a front plate 3 and a control plate 4. All three plates lie in mutually parallel planes, the control plate subdividing the interior of the jacket or shell 1 into two spaces, a forward post-acceleration space 5 and a rear gas discharge space.
  • the back plate 2 is provided on the front side thereof with a family of mutually parallel cathode strips 7 of relatively large area.
  • the front plate 3 supports, on the rear side thereof, a regular raster of phosphorus dots 8 which can be excited to light emission by electrons and, on the top thereof, a post-acceleration anode 9.
  • the control plate 4, which is braced against the front plate 3 by a spacer frame 10, is provided on the rear side thereof with a family of mutually parallel row conductors 11 and on the front side thereof with column conductors 12.
  • the row conductors 11 extend parallel to the cathode strips 7, and the column conductors 12 extend perpendicularly thereto.
  • Openings are formed in each of the conductors 11 and 12, namely electron inlet openings 13 in the row conductors 11 and electron outlet openings 14 in the column conductors 12.
  • the following voltages are applied to the individual electrodes: 200 volts and 0 volts, respectively, to the selected and non-selected cathode strips 7; 0 volts and -50 volts, respectively, to the keyed and no-keyed line conductors 11; between -80 volts and -30 volts to the column conductors 12; and +4 kV to the post-acceleration anode 9.
  • the electrode matrix is addressed line-by-line, row-by-row sequentially, and the cathode voltages are synchronized with the line or row scanning voltage in such a manner that the plasma burns, respectively, between the selected row conductor and the cathode strip which happens to be opposite it.
  • DE-OS Non-Prosecuted Application
  • U.S. Pat. No. 3,956,667 which, among other things, is also concerned in detail with questions of mechanical construction.
  • control plate 4 acts like a continuous plate when viewed perpendicularly to the planar extension thereof, because the openings on the one side thereof are covered-up by solid blinds or shutters on the other side thereof.
  • FIG. 2 in essence only the conductor part of the entire plate 4 is illustrated; of the conductor-carrying structure formed of insulating material, only column supports 25 which close the gaps between the column conductors are indicated).
  • Such a covering is effected if the following dimensions are selected: the row conductors 11 are 340 ⁇ m wide and are spaced 60 ⁇ m from one another.
  • the electron inlet openings 13 are rectangles with an area of 220 ⁇ 200 ⁇ m, the narrow sides of the rectangles being parallel to the extension of the row conductors, furthermore, the rectangles are spaced 200 ⁇ m from one another.
  • the column conductors are 340 ⁇ m wide, have a spacing likewise of 60 ⁇ m from one another and have slit-shaped electron outlet openings 14. These slits, which are parallel to the column conductors, are 300 ⁇ m long, 80 ⁇ m wide and are placed, respectively, behind one of the row conductor strips which remain between adjacent electron inlet openings.
  • the control plate 4 which is shown in FIG. 1 as an unstructured block in the interest of simplicity, should be constructed in practice so that it can, on the one hand, function as a stable support for the row and column conductors and, on the other hand, contain election passage channels which connect the mutually associated electron openings to one another.
  • the production of such a support structure presents no fundamental difficulties in practice because one may fall back on techniques which have already been developed for control discs with rectilinear cutouts.
  • the row and column conductors could be formed first on a thin glass foil and the glass could then be etched away through the conductor openings down to relatively small-area connecting points between the two families of conductors.
  • a second possibility is to realize the row and column conductors on separate support systems initially and, thereafter, to assemble these units in mutually correct position.
  • the support systems will contain mutually parallel insulating strips which are positioned, respectively, between two adjacent conductors and are optionally supplemented by a few transverse struts to form a self-supporting structure.
  • FIG. 2 shows the potential relationships in the vicinity of the electrode matrix and, specifically, for the case wherein the row conductor is selected and the column conductors are at passing potential. If the row conductor voltage is selected as the reference potential, the column conductors are at -30 volts. If the influences from the gas discharge space on the one hand and the post-acceleration space, on the other hand, are further added, a potential distribution is obtained, several characteristic equipotential surfaces of which are shown in the diagram of FIG. 2 and are provided therein with the corresponding potential values. Two saddle points of -5 volts, one approximately in the center of the electron beam inlet opening and another one above the electron outlet opening, are shown.
  • the saddle point located on the row conductor side and having a potential more positive than the potential surface generating it acts divergent for electrons and focusing for ions, whereas the saddle point located above the column opening and formed by a potential surface with more positive potential, focuses the electrons and scatters the ions.
  • These two lens effects change, in a characteristic manner, the trajectories of the charge carriers entering the control space.
  • representative trajectories of the electrons (curves 15, 16 and 17) and of ions (curves 18 and 19) have been introduced into the figure.
  • the curves 15 and 16 belong to slow electrons from the gas discharge; curve 17 designates the trajectory of a fast plasma electron; and the curves 18 and 19 describe the paths, respectively, of a fast and a braked-down ion from the post-acceleration space. It is apparent that the low-energy electrons are drawn through the control space on a curved trajectory and enter the post-acceleration space as a relatively well-focused beam. The slow electrons are initially scattered and, then, under the influence of a continuously pulling field, advanced to the inner side of the column conductors. The fast electrons and ions are deflected only slightly by the relatively weak fields; they impinge upon the parts of the control structure acting as shutters or blinds and are thereby rendered largely harmless.
  • the invention is, of course, not confined to the illustrated embodiment.
  • the openings on both sides of the control plate be set staggered with respect to one another.
  • the openings of the even-numbered row conductors could be offset relative to the openings of the odd-numbered line conductors, and the column conductors could correspondingly be made to extend in zig-zag fashion (note in this connection also German Pat. No. 26 15 569).

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  • Gas-Filled Discharge Tubes (AREA)
  • Lasers (AREA)
  • Analysing Materials By The Use Of Radiation (AREA)
  • Cathode-Ray Tubes And Fluorescent Screens For Display (AREA)
US06/505,308 1982-06-18 1983-06-17 Flat electron beam tube having a gas discharge as electron source Expired - Fee Related US4564790A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3222850 1982-06-18
DE19823222850 DE3222850A1 (de) 1982-06-18 1982-06-18 Flache elektronenstrahlroehre mit einer gasentladung als elektronenquelle

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US4564790A true US4564790A (en) 1986-01-14

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US (1) US4564790A (de)
EP (1) EP0097304B1 (de)
JP (1) JPS598250A (de)
AT (1) ATE26504T1 (de)
DE (2) DE3222850A1 (de)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4667130A (en) * 1984-02-21 1987-05-19 Siemens Aktiengesellschaft Flat gas discharge display
US4719388A (en) * 1985-08-13 1988-01-12 Source Technology Corporation Flat electron control device utilizing a uniform space-charge cloud of free electrons as a virtual cathode
WO1993021650A1 (en) * 1992-04-10 1993-10-28 Silicon Video Corporation Self supporting flat video display
US5386175A (en) * 1990-05-24 1995-01-31 U.S. Philips Corporation Thin-type picture display device
US5407210A (en) * 1993-11-15 1995-04-18 Canning; Robert P. Portable game apparatus for playing curb ball or other ball game
US5477105A (en) * 1992-04-10 1995-12-19 Silicon Video Corporation Structure of light-emitting device with raised black matrix for use in optical devices such as flat-panel cathode-ray tubes
US5672083A (en) * 1993-06-22 1997-09-30 Candescent Technologies Corporation Fabrication of flat panel device having backplate that includes ceramic layer

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3228183C2 (de) * 1982-07-28 1984-08-30 Siemens AG, 1000 Berlin und 8000 München Flache Elektronenstrahlröhre und Verfahren zu ihrer Herstellung
EP0167930A1 (de) * 1984-07-02 1986-01-15 Nokia Graetz Gesellschaft mit beschränkter Haftung Elektronensteuereinrichtung für Gasentladungsanzeigevorrichtung
DE3911346A1 (de) * 1989-04-07 1990-10-11 Nokia Unterhaltungselektronik Steuersystem fuer flache bildwiedergabevorrichtungen
US5256937A (en) * 1989-04-07 1993-10-26 Nokia (Deutschland) Gmbh Flat panel fluorescent screen display tube
DE3911343A1 (de) * 1989-04-07 1990-10-11 Nokia Unterhaltungselektronik Flache anzeigeeinrichtung

Citations (9)

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DE2412869A1 (de) * 1974-03-18 1975-10-02 Siemens Ag Entladungs-lumineszenz-anzeigeeinrichtung
DE2615569A1 (de) * 1976-04-09 1977-10-13 Siemens Ag Matrixadressierte gasentladungsanzeigevorrichtung zur mehrfarbigen darstellung von informationen
DE2643915A1 (de) * 1976-09-29 1978-03-30 Siemens Ag Bildanzeigeeinrichtung
DE2656621A1 (de) * 1976-12-14 1978-06-15 Siemens Ag Plasma-bildanzeigevorrichtung
DE2855056A1 (de) * 1978-12-20 1980-07-17 Siemens Ag Gasentladungsanzeigevorrichtung
US4236096A (en) * 1976-12-14 1980-11-25 Siemens Aktiengesellschaft Plasma image display device
DE3010179A1 (de) * 1980-03-17 1981-09-24 Siemens AG, 1000 Berlin und 8000 München Steuerscheibe fuer einen flachen plasmabildschirm
US4328444A (en) * 1979-06-29 1982-05-04 Siemens Aktiengesellschaft Gas discharge display device with a lamellar lattice in the gas discharge space
US4376258A (en) * 1981-04-16 1983-03-08 Rca Corporation Shielded beam guide structure for a flat panel display device and method of making same

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3845241A (en) * 1973-02-02 1974-10-29 Zenith Radio Corp Television display panel having gas discharge cathodo-luminescent elements

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2412869A1 (de) * 1974-03-18 1975-10-02 Siemens Ag Entladungs-lumineszenz-anzeigeeinrichtung
US3956667A (en) * 1974-03-18 1976-05-11 Siemens Aktiengesellschaft Luminous discharge display device
US3956667B1 (de) * 1974-03-18 1983-06-07
DE2615569A1 (de) * 1976-04-09 1977-10-13 Siemens Ag Matrixadressierte gasentladungsanzeigevorrichtung zur mehrfarbigen darstellung von informationen
DE2643915A1 (de) * 1976-09-29 1978-03-30 Siemens Ag Bildanzeigeeinrichtung
DE2656621A1 (de) * 1976-12-14 1978-06-15 Siemens Ag Plasma-bildanzeigevorrichtung
US4236096A (en) * 1976-12-14 1980-11-25 Siemens Aktiengesellschaft Plasma image display device
DE2855056A1 (de) * 1978-12-20 1980-07-17 Siemens Ag Gasentladungsanzeigevorrichtung
US4322657A (en) * 1978-12-20 1982-03-30 Siemens Aktiengesellschaft Gas-discharge display device
US4328444A (en) * 1979-06-29 1982-05-04 Siemens Aktiengesellschaft Gas discharge display device with a lamellar lattice in the gas discharge space
DE3010179A1 (de) * 1980-03-17 1981-09-24 Siemens AG, 1000 Berlin und 8000 München Steuerscheibe fuer einen flachen plasmabildschirm
US4376258A (en) * 1981-04-16 1983-03-08 Rca Corporation Shielded beam guide structure for a flat panel display device and method of making same

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4667130A (en) * 1984-02-21 1987-05-19 Siemens Aktiengesellschaft Flat gas discharge display
US4719388A (en) * 1985-08-13 1988-01-12 Source Technology Corporation Flat electron control device utilizing a uniform space-charge cloud of free electrons as a virtual cathode
US5386175A (en) * 1990-05-24 1995-01-31 U.S. Philips Corporation Thin-type picture display device
US5541473A (en) * 1992-04-10 1996-07-30 Silicon Video Corporation Grid addressed field emission cathode
US5477105A (en) * 1992-04-10 1995-12-19 Silicon Video Corporation Structure of light-emitting device with raised black matrix for use in optical devices such as flat-panel cathode-ray tubes
WO1993021650A1 (en) * 1992-04-10 1993-10-28 Silicon Video Corporation Self supporting flat video display
US5589731A (en) * 1992-04-10 1996-12-31 Silicon Video Corporation Internal support structure for flat panel device
US5597518A (en) * 1992-04-10 1997-01-28 Silicon Video Corporation Method for producing self supporting flat video display
US5674351A (en) * 1992-04-10 1997-10-07 Candescent Technologies Corporation Self supporting flat video display
US5798604A (en) * 1992-04-10 1998-08-25 Candescent Technologies Corporation Flat panel display with gate layer in contact with thicker patterned further conductive layer
US5672083A (en) * 1993-06-22 1997-09-30 Candescent Technologies Corporation Fabrication of flat panel device having backplate that includes ceramic layer
US5686790A (en) * 1993-06-22 1997-11-11 Candescent Technologies Corporation Flat panel device with ceramic backplate
US5407210A (en) * 1993-11-15 1995-04-18 Canning; Robert P. Portable game apparatus for playing curb ball or other ball game

Also Published As

Publication number Publication date
JPS598250A (ja) 1984-01-17
EP0097304A2 (de) 1984-01-04
DE3370896D1 (en) 1987-05-14
EP0097304A3 (en) 1984-10-17
ATE26504T1 (de) 1987-04-15
EP0097304B1 (de) 1987-04-08
DE3222850A1 (de) 1983-12-22

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